1. Technical Field
The present invention relates generally to speech recognition, and more particularly, to a voice-driven method and system for gathering information accessible via a network.
2. Description of the Related Art
Hypertext systems are rapidly increasing in significance in many areas of data and communications technology. Important examples which have already been realized include typical hypertext help systems and hypertext documentation for software applications as are commonly used with graphical operating systems for personal computers. To use these systems, a user typically navigates within single hypertext documents which are stored as data files on a single computer. Another example of a hypertext system is the World Wide Web (WWW), a worldwide hypertext network based on the Internet wherein users can navigate through a plurality of hypertext documents which are linked, cite, or reference one another. These hypertext documents are generally stored on a great number of computers in the network which are often located great distances from one another. Hypertext documents generally contain information in the form of text, digital images, audio and video data, and/or combinations thereof.
A significant characteristic feature of all hypertext systems is the possibility of navigation. In addition to containing the actual text of the document, a hypertext document contains special character sequences that can also be a component part of the actual text. These special character sequences are usually referred to as links or hyper-links and serve the purpose of hypertext navigation. Typically, these character sequences are specially marked. For example, hyperlinks can be displayed in a different color or can be emphasized in some other way, to distinguish the special character sequences from the ordinary text of the document. When a user of a hypertext system selects such a link, usually with a short click with the mouse or other pointing device, the hypertext system can react to this instruction by displaying, for example, the part of the same hypertext document or a different hypertext document which is associated with the character sequence (or link). Other possible reactions to selection of a link can include opening a connection to a different computer, for example to an on-line data bank, starting another application program, opening another data file, initiating a data processing process, or any combination thereof.
Hypertext systems also can execute other instructions which are not associated with the character sequences (links) in the hypertext documents. These instructions can include, for example, paging through documents or portions of documents which already have been displayed (for example, pages of the document), storing hypertext pages in what are referred to as hot lists, retrieving or paging through pages stored in hot lists, reloading images, and the like. Typically, these instructions are input in a manner commonly associated with graphic user interfaces, for example with a mouse or other pointing device.
There are a number of possible applications of hypertext-based systems wherein the traditional manner of inputting instructions or of activating links is considered to be disturbing, undesirable, or even impossible. Such can be the case when the user is impeded, the user's hands are busy with managing other jobs, or when the ambient conditions forbid the employment of traditional input devices. Voice recognition is available in such cases as a simple, natural type of input that assumes less expertise on the part of the user than other input means. The integration of traditional, acoustic voice recognition systems, i.e. systems for recognizing spoken language, with hypertext systems, which are also known as “viewer” or “browser” systems, are opposed by technological difficulties. For example, the voice recognition system must be able to recognize every word that can occur as a link in a hypertext document. Because practically every word in the text can also be a hyper-link, extremely large dictionaries would be required for this purpose. These large dictionaries would reduce the processing speed and the recognition performance of such a speech recognition system to an unjustifiable extent. Even if the employment of extremely large dictionaries were possible, recently coined or new words, as well as proper names may not be recognized. The use of new words and proper names, however, is typical with respect to many hypertext applications, particularly with hypertext networks such as the World Wide Web.
U.S. Pat. No. 6,029,135 discloses a hypertext navigation system for voice controlled navigation wherein a dictionary is provided which includes probability models for spoken words. The dictionary and probability model, which can include phoneme sequences to be matched to the spoken words is generated in the user's system during access to the hypertext document in the run time version. An off-line version provides a dictionary and a probability model that is generated, for example, by the author of the hypertext document. The model is stored on the server and is forwarded to the user system when the document is accessed by the user. The dictionary and probability model corresponds to the hypertext elements that are in the hypertext document which is being accessed by the user. Accordingly, the dictionary and probability model are discarded and the next dictionary and probability model are obtained as the next hypertext document is accessed. Storage of recent or important dictionaries and probability models are also provided.
One disadvantage of the above-mentioned system is that the voice recognition is mainly restricted to the hyperlinks used in the hypertext document being accessed by the user. Other hyperlinks which are not visible on the hypertext document being accessed cannot be recognized. Furthermore, such prior art systems cannot accommodate forms which can be filled out by a user.
It is therefore object of the present invention to provide a hypertext navigation system combining the advantages of point and click hypertext navigation system with prior art voice controlled hypertext navigation system by avoiding their disadvantages.